| abstract |
A polyvalent vaccine effective in immunization of bovines against infectious bovine rhinotracheitis virus (IBR), bovine viral diarrhea virus (BVD) and parainfluenza-3 virus (PI-3) is composed of a suspension, in a vehicle such as an aqueous solution of formaldehyde suitable for parenteral injection of the three viruses in killed form. The three viruses are separately propagated and subsequently suspended in aqueous solutions containing 0.4 percent by volume formalin, and the respective suspensions are maintained at a temperature of about 4*C. for 1 week. Portions, for example equal portions, of the three suspensions are combined to produce a polyvalent vaccine. An equal volume of an aqueous solution containing from 1 to 5 percent weight/volume of a soluble alginate, such as sodium alginate, having certain specified properties may be added to the vaccine as an adjuvant to enhance its effectiveness. Such polyvalent vaccines are adapted for parenteral administration in the vaccination of bovines. |